/
qemu-options.hx
3378 lines (2871 loc) · 125 KB
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qemu-options.hx
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HXCOMM Use DEFHEADING() to define headings in both help text and texi
HXCOMM Text between STEXI and ETEXI are copied to texi version and
HXCOMM discarded from C version
HXCOMM DEF(option, HAS_ARG/0, opt_enum, opt_help, arch_mask) is used to
HXCOMM construct option structures, enums and help message for specified
HXCOMM architectures.
HXCOMM HXCOMM can be used for comments, discarded from both texi and C
DEFHEADING(Standard options:)
STEXI
@table @option
ETEXI
DEF("help", 0, QEMU_OPTION_h,
"-h or -help display this help and exit\n", QEMU_ARCH_ALL)
STEXI
@item -h
@findex -h
Display help and exit
ETEXI
DEF("version", 0, QEMU_OPTION_version,
"-version display version information and exit\n", QEMU_ARCH_ALL)
STEXI
@item -version
@findex -version
Display version information and exit
ETEXI
DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
"-machine [type=]name[,prop[=value][,...]]\n"
" selects emulated machine ('-machine help' for list)\n"
" property accel=accel1[:accel2[:...]] selects accelerator\n"
" supported accelerators are kvm, xen, tcg (default: tcg)\n"
" kernel_irqchip=on|off controls accelerated irqchip support\n"
" kvm_shadow_mem=size of KVM shadow MMU\n"
" dump-guest-core=on|off include guest memory in a core dump (default=on)\n"
" mem-merge=on|off controls memory merge support (default: on)\n"
" iommu=on|off controls emulated Intel IOMMU (VT-d) support (default=off)\n",
QEMU_ARCH_ALL)
STEXI
@item -machine [type=]@var{name}[,prop=@var{value}[,...]]
@findex -machine
Select the emulated machine by @var{name}. Use @code{-machine help} to list
available machines. Supported machine properties are:
@table @option
@item accel=@var{accels1}[:@var{accels2}[:...]]
This is used to enable an accelerator. Depending on the target architecture,
kvm, xen, or tcg can be available. By default, tcg is used. If there is more
than one accelerator specified, the next one is used if the previous one fails
to initialize.
@item kernel_irqchip=on|off
Enables in-kernel irqchip support for the chosen accelerator when available.
@item kvm_shadow_mem=size
Defines the size of the KVM shadow MMU.
@item dump-guest-core=on|off
Include guest memory in a core dump. The default is on.
@item mem-merge=on|off
Enables or disables memory merge support. This feature, when supported by
the host, de-duplicates identical memory pages among VMs instances
(enabled by default).
@item iommu=on|off
Enables or disables emulated Intel IOMMU (VT-d) support. The default is off.
@end table
ETEXI
HXCOMM Deprecated by -machine
DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL)
DEF("cpu", HAS_ARG, QEMU_OPTION_cpu,
"-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL)
STEXI
@item -cpu @var{model}
@findex -cpu
Select CPU model (@code{-cpu help} for list and additional feature selection)
ETEXI
DEF("smp", HAS_ARG, QEMU_OPTION_smp,
"-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n"
" set the number of CPUs to 'n' [default=1]\n"
" maxcpus= maximum number of total cpus, including\n"
" offline CPUs for hotplug, etc\n"
" cores= number of CPU cores on one socket\n"
" threads= number of threads on one CPU core\n"
" sockets= number of discrete sockets in the system\n",
QEMU_ARCH_ALL)
STEXI
@item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}]
@findex -smp
Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255
CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs
to 4.
For the PC target, the number of @var{cores} per socket, the number
of @var{threads} per cores and the total number of @var{sockets} can be
specified. Missing values will be computed. If any on the three values is
given, the total number of CPUs @var{n} can be omitted. @var{maxcpus}
specifies the maximum number of hotpluggable CPUs.
ETEXI
DEF("numa", HAS_ARG, QEMU_OPTION_numa,
"-numa node[,mem=size][,cpus=cpu[-cpu]][,nodeid=node]\n"
"-numa node[,memdev=id][,cpus=cpu[-cpu]][,nodeid=node]\n", QEMU_ARCH_ALL)
STEXI
@item -numa node[,mem=@var{size}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}]
@item -numa node[,memdev=@var{id}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}]
@findex -numa
Simulate a multi node NUMA system. If @samp{mem}, @samp{memdev}
and @samp{cpus} are omitted, resources are split equally. Also, note
that the -@option{numa} option doesn't allocate any of the specified
resources. That is, it just assigns existing resources to NUMA nodes. This
means that one still has to use the @option{-m}, @option{-smp} options
to allocate RAM and VCPUs respectively, and possibly @option{-object}
to specify the memory backend for the @samp{memdev} suboption.
@samp{mem} and @samp{memdev} are mutually exclusive. Furthermore, if one
node uses @samp{memdev}, all of them have to use it.
ETEXI
DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd,
"-add-fd fd=fd,set=set[,opaque=opaque]\n"
" Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL)
STEXI
@item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}]
@findex -add-fd
Add a file descriptor to an fd set. Valid options are:
@table @option
@item fd=@var{fd}
This option defines the file descriptor of which a duplicate is added to fd set.
The file descriptor cannot be stdin, stdout, or stderr.
@item set=@var{set}
This option defines the ID of the fd set to add the file descriptor to.
@item opaque=@var{opaque}
This option defines a free-form string that can be used to describe @var{fd}.
@end table
You can open an image using pre-opened file descriptors from an fd set:
@example
qemu-system-i386
-add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
-add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
-drive file=/dev/fdset/2,index=0,media=disk
@end example
ETEXI
DEF("set", HAS_ARG, QEMU_OPTION_set,
"-set group.id.arg=value\n"
" set <arg> parameter for item <id> of type <group>\n"
" i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL)
STEXI
@item -set @var{group}.@var{id}.@var{arg}=@var{value}
@findex -set
Set parameter @var{arg} for item @var{id} of type @var{group}\n"
ETEXI
DEF("global", HAS_ARG, QEMU_OPTION_global,
"-global driver.prop=value\n"
" set a global default for a driver property\n",
QEMU_ARCH_ALL)
STEXI
@item -global @var{driver}.@var{prop}=@var{value}
@findex -global
Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.:
@example
qemu-system-i386 -global ide-drive.physical_block_size=4096 -drive file=file,if=ide,index=0,media=disk
@end example
In particular, you can use this to set driver properties for devices which are
created automatically by the machine model. To create a device which is not
created automatically and set properties on it, use -@option{device}.
ETEXI
DEF("boot", HAS_ARG, QEMU_OPTION_boot,
"-boot [order=drives][,once=drives][,menu=on|off]\n"
" [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n"
" 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n"
" 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n"
" 'sp_time': the period that splash picture last if menu=on, unit is ms\n"
" 'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n",
QEMU_ARCH_ALL)
STEXI
@item -boot [order=@var{drives}][,once=@var{drives}][,menu=on|off][,splash=@var{sp_name}][,splash-time=@var{sp_time}][,reboot-timeout=@var{rb_timeout}][,strict=on|off]
@findex -boot
Specify boot order @var{drives} as a string of drive letters. Valid
drive letters depend on the target achitecture. The x86 PC uses: a, b
(floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot
from network adapter 1-4), hard disk boot is the default. To apply a
particular boot order only on the first startup, specify it via
@option{once}.
Interactive boot menus/prompts can be enabled via @option{menu=on} as far
as firmware/BIOS supports them. The default is non-interactive boot.
A splash picture could be passed to bios, enabling user to show it as logo,
when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS
supports them. Currently Seabios for X86 system support it.
limitation: The splash file could be a jpeg file or a BMP file in 24 BPP
format(true color). The resolution should be supported by the SVGA mode, so
the recommended is 320x240, 640x480, 800x640.
A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms
when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not
reboot, qemu passes '-1' to bios by default. Currently Seabios for X86
system support it.
Do strict boot via @option{strict=on} as far as firmware/BIOS
supports it. This only effects when boot priority is changed by
bootindex options. The default is non-strict boot.
@example
# try to boot from network first, then from hard disk
qemu-system-i386 -boot order=nc
# boot from CD-ROM first, switch back to default order after reboot
qemu-system-i386 -boot once=d
# boot with a splash picture for 5 seconds.
qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000
@end example
Note: The legacy format '-boot @var{drives}' is still supported but its
use is discouraged as it may be removed from future versions.
ETEXI
DEF("m", HAS_ARG, QEMU_OPTION_m,
"-m[emory] [size=]megs[,slots=n,maxmem=size]\n"
" configure guest RAM\n"
" size: initial amount of guest memory (default: "
stringify(DEFAULT_RAM_SIZE) "MiB)\n"
" slots: number of hotplug slots (default: none)\n"
" maxmem: maximum amount of guest memory (default: none)\n"
"NOTE: Some architectures might enforce a specific granularity\n",
QEMU_ARCH_ALL)
STEXI
@item -m [size=]@var{megs}
@findex -m
Set virtual RAM size to @var{megs} megabytes. Default is 128 MiB. Optionally,
a suffix of ``M'' or ``G'' can be used to signify a value in megabytes or
gigabytes respectively. Optional pair @var{slots}, @var{maxmem} could be used
to set amount of hotluggable memory slots and possible maximum amount of memory.
ETEXI
DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath,
"-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL)
STEXI
@item -mem-path @var{path}
@findex -mem-path
Allocate guest RAM from a temporarily created file in @var{path}.
ETEXI
DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc,
"-mem-prealloc preallocate guest memory (use with -mem-path)\n",
QEMU_ARCH_ALL)
STEXI
@item -mem-prealloc
@findex -mem-prealloc
Preallocate memory when using -mem-path.
ETEXI
DEF("k", HAS_ARG, QEMU_OPTION_k,
"-k language use keyboard layout (for example 'fr' for French)\n",
QEMU_ARCH_ALL)
STEXI
@item -k @var{language}
@findex -k
Use keyboard layout @var{language} (for example @code{fr} for
French). This option is only needed where it is not easy to get raw PC
keycodes (e.g. on Macs, with some X11 servers or with a VNC
display). You don't normally need to use it on PC/Linux or PC/Windows
hosts.
The available layouts are:
@example
ar de-ch es fo fr-ca hu ja mk no pt-br sv
da en-gb et fr fr-ch is lt nl pl ru th
de en-us fi fr-be hr it lv nl-be pt sl tr
@end example
The default is @code{en-us}.
ETEXI
DEF("audio-help", 0, QEMU_OPTION_audio_help,
"-audio-help print list of audio drivers and their options\n",
QEMU_ARCH_ALL)
STEXI
@item -audio-help
@findex -audio-help
Will show the audio subsystem help: list of drivers, tunable
parameters.
ETEXI
DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw,
"-soundhw c1,... enable audio support\n"
" and only specified sound cards (comma separated list)\n"
" use '-soundhw help' to get the list of supported cards\n"
" use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL)
STEXI
@item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
@findex -soundhw
Enable audio and selected sound hardware. Use 'help' to print all
available sound hardware.
@example
qemu-system-i386 -soundhw sb16,adlib disk.img
qemu-system-i386 -soundhw es1370 disk.img
qemu-system-i386 -soundhw ac97 disk.img
qemu-system-i386 -soundhw hda disk.img
qemu-system-i386 -soundhw all disk.img
qemu-system-i386 -soundhw help
@end example
Note that Linux's i810_audio OSS kernel (for AC97) module might
require manually specifying clocking.
@example
modprobe i810_audio clocking=48000
@end example
ETEXI
DEF("balloon", HAS_ARG, QEMU_OPTION_balloon,
"-balloon none disable balloon device\n"
"-balloon virtio[,addr=str]\n"
" enable virtio balloon device (default)\n", QEMU_ARCH_ALL)
STEXI
@item -balloon none
@findex -balloon
Disable balloon device.
@item -balloon virtio[,addr=@var{addr}]
Enable virtio balloon device (default), optionally with PCI address
@var{addr}.
ETEXI
DEF("device", HAS_ARG, QEMU_OPTION_device,
"-device driver[,prop[=value][,...]]\n"
" add device (based on driver)\n"
" prop=value,... sets driver properties\n"
" use '-device help' to print all possible drivers\n"
" use '-device driver,help' to print all possible properties\n",
QEMU_ARCH_ALL)
STEXI
@item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
@findex -device
Add device @var{driver}. @var{prop}=@var{value} sets driver
properties. Valid properties depend on the driver. To get help on
possible drivers and properties, use @code{-device help} and
@code{-device @var{driver},help}.
ETEXI
DEF("name", HAS_ARG, QEMU_OPTION_name,
"-name string1[,process=string2][,debug-threads=on|off]\n"
" set the name of the guest\n"
" string1 sets the window title and string2 the process name (on Linux)\n"
" When debug-threads is enabled, individual threads are given a separate name (on Linux)\n"
" NOTE: The thread names are for debugging and not a stable API.\n",
QEMU_ARCH_ALL)
STEXI
@item -name @var{name}
@findex -name
Sets the @var{name} of the guest.
This name will be displayed in the SDL window caption.
The @var{name} will also be used for the VNC server.
Also optionally set the top visible process name in Linux.
Naming of individual threads can also be enabled on Linux to aid debugging.
ETEXI
DEF("uuid", HAS_ARG, QEMU_OPTION_uuid,
"-uuid %08x-%04x-%04x-%04x-%012x\n"
" specify machine UUID\n", QEMU_ARCH_ALL)
STEXI
@item -uuid @var{uuid}
@findex -uuid
Set system UUID.
ETEXI
STEXI
@end table
ETEXI
DEFHEADING()
DEFHEADING(Block device options:)
STEXI
@table @option
ETEXI
DEF("fda", HAS_ARG, QEMU_OPTION_fda,
"-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL)
DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL)
STEXI
@item -fda @var{file}
@item -fdb @var{file}
@findex -fda
@findex -fdb
Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). You can
use the host floppy by using @file{/dev/fd0} as filename (@pxref{host_drives}).
ETEXI
DEF("hda", HAS_ARG, QEMU_OPTION_hda,
"-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL)
DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL)
DEF("hdc", HAS_ARG, QEMU_OPTION_hdc,
"-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL)
DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL)
STEXI
@item -hda @var{file}
@item -hdb @var{file}
@item -hdc @var{file}
@item -hdd @var{file}
@findex -hda
@findex -hdb
@findex -hdc
@findex -hdd
Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
ETEXI
DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom,
"-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n",
QEMU_ARCH_ALL)
STEXI
@item -cdrom @var{file}
@findex -cdrom
Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
@option{-cdrom} at the same time). You can use the host CD-ROM by
using @file{/dev/cdrom} as filename (@pxref{host_drives}).
ETEXI
DEF("drive", HAS_ARG, QEMU_OPTION_drive,
"-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
" [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n"
" [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n"
" [,serial=s][,addr=A][,rerror=ignore|stop|report]\n"
" [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n"
" [,readonly=on|off][,copy-on-read=on|off]\n"
" [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n"
" [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n"
" [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n"
" [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n"
" [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n"
" [[,iops_size=is]]\n"
" use 'file' as a drive image\n", QEMU_ARCH_ALL)
STEXI
@item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
@findex -drive
Define a new drive. Valid options are:
@table @option
@item file=@var{file}
This option defines which disk image (@pxref{disk_images}) to use with
this drive. If the filename contains comma, you must double it
(for instance, "file=my,,file" to use file "my,file").
Special files such as iSCSI devices can be specified using protocol
specific URLs. See the section for "Device URL Syntax" for more information.
@item if=@var{interface}
This option defines on which type on interface the drive is connected.
Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio.
@item bus=@var{bus},unit=@var{unit}
These options define where is connected the drive by defining the bus number and
the unit id.
@item index=@var{index}
This option defines where is connected the drive by using an index in the list
of available connectors of a given interface type.
@item media=@var{media}
This option defines the type of the media: disk or cdrom.
@item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
These options have the same definition as they have in @option{-hdachs}.
@item snapshot=@var{snapshot}
@var{snapshot} is "on" or "off" and controls snapshot mode for the given drive
(see @option{-snapshot}).
@item cache=@var{cache}
@var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" and controls how the host cache is used to access block data.
@item aio=@var{aio}
@var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO.
@item discard=@var{discard}
@var{discard} is one of "ignore" (or "off") or "unmap" (or "on") and controls whether @dfn{discard} (also known as @dfn{trim} or @dfn{unmap}) requests are ignored or passed to the filesystem. Some machine types may not support discard requests.
@item format=@var{format}
Specify which disk @var{format} will be used rather than detecting
the format. Can be used to specifiy format=raw to avoid interpreting
an untrusted format header.
@item serial=@var{serial}
This option specifies the serial number to assign to the device.
@item addr=@var{addr}
Specify the controller's PCI address (if=virtio only).
@item werror=@var{action},rerror=@var{action}
Specify which @var{action} to take on write and read errors. Valid actions are:
"ignore" (ignore the error and try to continue), "stop" (pause QEMU),
"report" (report the error to the guest), "enospc" (pause QEMU only if the
host disk is full; report the error to the guest otherwise).
The default setting is @option{werror=enospc} and @option{rerror=report}.
@item readonly
Open drive @option{file} as read-only. Guest write attempts will fail.
@item copy-on-read=@var{copy-on-read}
@var{copy-on-read} is "on" or "off" and enables whether to copy read backing
file sectors into the image file.
@item detect-zeroes=@var{detect-zeroes}
@var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic
conversion of plain zero writes by the OS to driver specific optimized
zero write commands. You may even choose "unmap" if @var{discard} is set
to "unmap" to allow a zero write to be converted to an UNMAP operation.
@end table
By default, the @option{cache=writeback} mode is used. It will report data
writes as completed as soon as the data is present in the host page cache.
This is safe as long as your guest OS makes sure to correctly flush disk caches
where needed. If your guest OS does not handle volatile disk write caches
correctly and your host crashes or loses power, then the guest may experience
data corruption.
For such guests, you should consider using @option{cache=writethrough}. This
means that the host page cache will be used to read and write data, but write
notification will be sent to the guest only after QEMU has made sure to flush
each write to the disk. Be aware that this has a major impact on performance.
The host page cache can be avoided entirely with @option{cache=none}. This will
attempt to do disk IO directly to the guest's memory. QEMU may still perform
an internal copy of the data. Note that this is considered a writeback mode and
the guest OS must handle the disk write cache correctly in order to avoid data
corruption on host crashes.
The host page cache can be avoided while only sending write notifications to
the guest when the data has been flushed to the disk using
@option{cache=directsync}.
In case you don't care about data integrity over host failures, use
@option{cache=unsafe}. This option tells QEMU that it never needs to write any
data to the disk but can instead keep things in cache. If anything goes wrong,
like your host losing power, the disk storage getting disconnected accidentally,
etc. your image will most probably be rendered unusable. When using
the @option{-snapshot} option, unsafe caching is always used.
Copy-on-read avoids accessing the same backing file sectors repeatedly and is
useful when the backing file is over a slow network. By default copy-on-read
is off.
Instead of @option{-cdrom} you can use:
@example
qemu-system-i386 -drive file=file,index=2,media=cdrom
@end example
Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
use:
@example
qemu-system-i386 -drive file=file,index=0,media=disk
qemu-system-i386 -drive file=file,index=1,media=disk
qemu-system-i386 -drive file=file,index=2,media=disk
qemu-system-i386 -drive file=file,index=3,media=disk
@end example
You can open an image using pre-opened file descriptors from an fd set:
@example
qemu-system-i386
-add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
-add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
-drive file=/dev/fdset/2,index=0,media=disk
@end example
You can connect a CDROM to the slave of ide0:
@example
qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
@end example
If you don't specify the "file=" argument, you define an empty drive:
@example
qemu-system-i386 -drive if=ide,index=1,media=cdrom
@end example
You can connect a SCSI disk with unit ID 6 on the bus #0:
@example
qemu-system-i386 -drive file=file,if=scsi,bus=0,unit=6
@end example
Instead of @option{-fda}, @option{-fdb}, you can use:
@example
qemu-system-i386 -drive file=file,index=0,if=floppy
qemu-system-i386 -drive file=file,index=1,if=floppy
@end example
By default, @var{interface} is "ide" and @var{index} is automatically
incremented:
@example
qemu-system-i386 -drive file=a -drive file=b"
@end example
is interpreted like:
@example
qemu-system-i386 -hda a -hdb b
@end example
ETEXI
DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock,
"-mtdblock file use 'file' as on-board Flash memory image\n",
QEMU_ARCH_ALL)
STEXI
@item -mtdblock @var{file}
@findex -mtdblock
Use @var{file} as on-board Flash memory image.
ETEXI
DEF("sd", HAS_ARG, QEMU_OPTION_sd,
"-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL)
STEXI
@item -sd @var{file}
@findex -sd
Use @var{file} as SecureDigital card image.
ETEXI
DEF("pflash", HAS_ARG, QEMU_OPTION_pflash,
"-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL)
STEXI
@item -pflash @var{file}
@findex -pflash
Use @var{file} as a parallel flash image.
ETEXI
DEF("snapshot", 0, QEMU_OPTION_snapshot,
"-snapshot write to temporary files instead of disk image files\n",
QEMU_ARCH_ALL)
STEXI
@item -snapshot
@findex -snapshot
Write to temporary files instead of disk image files. In this case,
the raw disk image you use is not written back. You can however force
the write back by pressing @key{C-a s} (@pxref{disk_images}).
ETEXI
DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \
"-hdachs c,h,s[,t]\n" \
" force hard disk 0 physical geometry and the optional BIOS\n" \
" translation (t=none or lba) (usually QEMU can guess them)\n",
QEMU_ARCH_ALL)
STEXI
@item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
@findex -hdachs
Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
@var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
all those parameters. This option is useful for old MS-DOS disk
images.
ETEXI
DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev,
"-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
" [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
QEMU_ARCH_ALL)
STEXI
@item -fsdev @var{fsdriver},id=@var{id},path=@var{path},[security_model=@var{security_model}][,writeout=@var{writeout}][,readonly][,socket=@var{socket}|sock_fd=@var{sock_fd}]
@findex -fsdev
Define a new file system device. Valid options are:
@table @option
@item @var{fsdriver}
This option specifies the fs driver backend to use.
Currently "local", "handle" and "proxy" file system drivers are supported.
@item id=@var{id}
Specifies identifier for this device
@item path=@var{path}
Specifies the export path for the file system device. Files under
this path will be available to the 9p client on the guest.
@item security_model=@var{security_model}
Specifies the security model to be used for this export path.
Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
In "passthrough" security model, files are stored using the same
credentials as they are created on the guest. This requires QEMU
to run as root. In "mapped-xattr" security model, some of the file
attributes like uid, gid, mode bits and link target are stored as
file attributes. For "mapped-file" these attributes are stored in the
hidden .virtfs_metadata directory. Directories exported by this security model cannot
interact with other unix tools. "none" security model is same as
passthrough except the sever won't report failures if it fails to
set file attributes like ownership. Security model is mandatory
only for local fsdriver. Other fsdrivers (like handle, proxy) don't take
security model as a parameter.
@item writeout=@var{writeout}
This is an optional argument. The only supported value is "immediate".
This means that host page cache will be used to read and write data but
write notification will be sent to the guest only when the data has been
reported as written by the storage subsystem.
@item readonly
Enables exporting 9p share as a readonly mount for guests. By default
read-write access is given.
@item socket=@var{socket}
Enables proxy filesystem driver to use passed socket file for communicating
with virtfs-proxy-helper
@item sock_fd=@var{sock_fd}
Enables proxy filesystem driver to use passed socket descriptor for
communicating with virtfs-proxy-helper. Usually a helper like libvirt
will create socketpair and pass one of the fds as sock_fd
@end table
-fsdev option is used along with -device driver "virtio-9p-pci".
@item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag}
Options for virtio-9p-pci driver are:
@table @option
@item fsdev=@var{id}
Specifies the id value specified along with -fsdev option
@item mount_tag=@var{mount_tag}
Specifies the tag name to be used by the guest to mount this export point
@end table
ETEXI
DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs,
"-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
" [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
QEMU_ARCH_ALL)
STEXI
@item -virtfs @var{fsdriver}[,path=@var{path}],mount_tag=@var{mount_tag}[,security_model=@var{security_model}][,writeout=@var{writeout}][,readonly][,socket=@var{socket}|sock_fd=@var{sock_fd}]
@findex -virtfs
The general form of a Virtual File system pass-through options are:
@table @option
@item @var{fsdriver}
This option specifies the fs driver backend to use.
Currently "local", "handle" and "proxy" file system drivers are supported.
@item id=@var{id}
Specifies identifier for this device
@item path=@var{path}
Specifies the export path for the file system device. Files under
this path will be available to the 9p client on the guest.
@item security_model=@var{security_model}
Specifies the security model to be used for this export path.
Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
In "passthrough" security model, files are stored using the same
credentials as they are created on the guest. This requires QEMU
to run as root. In "mapped-xattr" security model, some of the file
attributes like uid, gid, mode bits and link target are stored as
file attributes. For "mapped-file" these attributes are stored in the
hidden .virtfs_metadata directory. Directories exported by this security model cannot
interact with other unix tools. "none" security model is same as
passthrough except the sever won't report failures if it fails to
set file attributes like ownership. Security model is mandatory only
for local fsdriver. Other fsdrivers (like handle, proxy) don't take security
model as a parameter.
@item writeout=@var{writeout}
This is an optional argument. The only supported value is "immediate".
This means that host page cache will be used to read and write data but
write notification will be sent to the guest only when the data has been
reported as written by the storage subsystem.
@item readonly
Enables exporting 9p share as a readonly mount for guests. By default
read-write access is given.
@item socket=@var{socket}
Enables proxy filesystem driver to use passed socket file for
communicating with virtfs-proxy-helper. Usually a helper like libvirt
will create socketpair and pass one of the fds as sock_fd
@item sock_fd
Enables proxy filesystem driver to use passed 'sock_fd' as the socket
descriptor for interfacing with virtfs-proxy-helper
@end table
ETEXI
DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth,
"-virtfs_synth Create synthetic file system image\n",
QEMU_ARCH_ALL)
STEXI
@item -virtfs_synth
@findex -virtfs_synth
Create synthetic file system image
ETEXI
STEXI
@end table
ETEXI
DEFHEADING()
DEFHEADING(USB options:)
STEXI
@table @option
ETEXI
DEF("usb", 0, QEMU_OPTION_usb,
"-usb enable the USB driver (will be the default soon)\n",
QEMU_ARCH_ALL)
STEXI
@item -usb
@findex -usb
Enable the USB driver (will be the default soon)
ETEXI
DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice,
"-usbdevice name add the host or guest USB device 'name'\n",
QEMU_ARCH_ALL)
STEXI
@item -usbdevice @var{devname}
@findex -usbdevice
Add the USB device @var{devname}. @xref{usb_devices}.
@table @option
@item mouse
Virtual Mouse. This will override the PS/2 mouse emulation when activated.
@item tablet
Pointer device that uses absolute coordinates (like a touchscreen). This
means QEMU is able to report the mouse position without having to grab the
mouse. Also overrides the PS/2 mouse emulation when activated.
@item disk:[format=@var{format}]:@var{file}
Mass storage device based on file. The optional @var{format} argument
will be used rather than detecting the format. Can be used to specifiy
@code{format=raw} to avoid interpreting an untrusted format header.
@item host:@var{bus}.@var{addr}
Pass through the host device identified by @var{bus}.@var{addr} (Linux only).
@item host:@var{vendor_id}:@var{product_id}
Pass through the host device identified by @var{vendor_id}:@var{product_id}
(Linux only).
@item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
Serial converter to host character device @var{dev}, see @code{-serial} for the
available devices.
@item braille
Braille device. This will use BrlAPI to display the braille output on a real
or fake device.
@item net:@var{options}
Network adapter that supports CDC ethernet and RNDIS protocols.
@end table
ETEXI
STEXI
@end table
ETEXI
DEFHEADING()
DEFHEADING(Display options:)
STEXI
@table @option
ETEXI
DEF("display", HAS_ARG, QEMU_OPTION_display,
"-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
" [,window_close=on|off]|curses|none|\n"
" gtk[,grab_on_hover=on|off]|\n"
" vnc=<display>[,<optargs>]\n"
" select display type\n", QEMU_ARCH_ALL)
STEXI
@item -display @var{type}
@findex -display
Select type of display to use. This option is a replacement for the
old style -sdl/-curses/... options. Valid values for @var{type} are
@table @option
@item sdl
Display video output via SDL (usually in a separate graphics
window; see the SDL documentation for other possibilities).
@item curses
Display video output via curses. For graphics device models which
support a text mode, QEMU can display this output using a
curses/ncurses interface. Nothing is displayed when the graphics
device is in graphical mode or if the graphics device does not support
a text mode. Generally only the VGA device models support text mode.
@item none
Do not display video output. The guest will still see an emulated
graphics card, but its output will not be displayed to the QEMU
user. This option differs from the -nographic option in that it
only affects what is done with video output; -nographic also changes
the destination of the serial and parallel port data.
@item gtk
Display video output in a GTK window. This interface provides drop-down
menus and other UI elements to configure and control the VM during
runtime.
@item vnc
Start a VNC server on display <arg>
@end table
ETEXI
DEF("nographic", 0, QEMU_OPTION_nographic,
"-nographic disable graphical output and redirect serial I/Os to console\n",
QEMU_ARCH_ALL)
STEXI
@item -nographic
@findex -nographic
Normally, QEMU uses SDL to display the VGA output. With this option,
you can totally disable graphical output so that QEMU is a simple
command line application. The emulated serial port is redirected on
the console and muxed with the monitor (unless redirected elsewhere
explicitly). Therefore, you can still use QEMU to debug a Linux kernel
with a serial console. Use @key{C-a h} for help on switching between
the console and monitor.
ETEXI
DEF("curses", 0, QEMU_OPTION_curses,
"-curses use a curses/ncurses interface instead of SDL\n",
QEMU_ARCH_ALL)
STEXI
@item -curses
@findex -curses
Normally, QEMU uses SDL to display the VGA output. With this option,
QEMU can display the VGA output when in text mode using a
curses/ncurses interface. Nothing is displayed in graphical mode.
ETEXI
DEF("no-frame", 0, QEMU_OPTION_no_frame,
"-no-frame open SDL window without a frame and window decorations\n",
QEMU_ARCH_ALL)
STEXI
@item -no-frame
@findex -no-frame
Do not use decorations for SDL windows and start them using the whole
available screen space. This makes the using QEMU in a dedicated desktop
workspace more convenient.
ETEXI
DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
"-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
QEMU_ARCH_ALL)
STEXI
@item -alt-grab
@findex -alt-grab
Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
affects the special keys (for fullscreen, monitor-mode switching, etc).
ETEXI
DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
"-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
QEMU_ARCH_ALL)
STEXI
@item -ctrl-grab
@findex -ctrl-grab
Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also
affects the special keys (for fullscreen, monitor-mode switching, etc).
ETEXI
DEF("no-quit", 0, QEMU_OPTION_no_quit,
"-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL)
STEXI
@item -no-quit
@findex -no-quit
Disable SDL window close capability.
ETEXI
DEF("sdl", 0, QEMU_OPTION_sdl,
"-sdl enable SDL\n", QEMU_ARCH_ALL)
STEXI
@item -sdl
@findex -sdl
Enable SDL.
ETEXI
DEF("spice", HAS_ARG, QEMU_OPTION_spice,
"-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
" [,x509-key-file=<file>][,x509-key-password=<file>]\n"
" [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
" [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6]\n"
" [,tls-ciphers=<list>]\n"
" [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
" [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
" [,sasl][,password=<secret>][,disable-ticketing]\n"
" [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
" [,jpeg-wan-compression=[auto|never|always]]\n"
" [,zlib-glz-wan-compression=[auto|never|always]]\n"
" [,streaming-video=[off|all|filter]][,disable-copy-paste]\n"
" [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n"
" [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n"
" enable spice\n"
" at least one of {port, tls-port} is mandatory\n",
QEMU_ARCH_ALL)
STEXI
@item -spice @var{option}[,@var{option}[,...]]
@findex -spice
Enable the spice remote desktop protocol. Valid options are
@table @option
@item port=<nr>
Set the TCP port spice is listening on for plaintext channels.
@item addr=<addr>
Set the IP address spice is listening on. Default is any address.
@item ipv4
@item ipv6
Force using the specified IP version.
@item password=<secret>
Set the password you need to authenticate.
@item sasl
Require that the client use SASL to authenticate with the spice.
The exact choice of authentication method used is controlled from the
system / user's SASL configuration file for the 'qemu' service. This
is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
unprivileged user, an environment variable SASL_CONF_PATH can be used
to make it search alternate locations for the service config.
While some SASL auth methods can also provide data encryption (eg GSSAPI),
it is recommended that SASL always be combined with the 'tls' and
'x509' settings to enable use of SSL and server certificates. This
ensures a data encryption preventing compromise of authentication
credentials.
@item disable-ticketing
Allow client connects without authentication.